Inkjet imaging devices eject liquid ink from printheads to form images on an image receiving member. The printheads include a plurality of inkjets that are arranged in some type of array. Each inkjet has a thermal or piezoelectric actuator that is coupled to a printhead controller. The printhead controller generates firing signals that correspond to digital data for images. The frequency and amplitude of the firing signals correspond to the selective activation of the printhead actuators. The printhead actuators respond to the firing signals by ejecting ink drops onto an image receiving member to form an ink image that corresponds to the digital image used to generate the firing signals.
Some embodiments of inkjet printers include printheads that receive ink for ejection onto a continuously moving image receiving substrate. One such inkjet printer is a continuous web printing device. In these systems, a continuous media substrate, such as a paper web, moves through a print zone where one or more printheads form ink images on the surface of the media substrate. In some embodiments, the media substrate may move through the print zone at a rate of several hundred feet per minute.
During operation, faults may develop in systems that supply ink to printheads in the printer. If one or more printheads do not receive a sufficient supply of ink, then the media substrate may pass the printheads without receiving a full ink image. The portion of the media substrate that is not fully imaged may have to be discarded. Previously known printers stop the media web when a fault in the ink supply is detected. Stopping the media web requires any faults in the ink supply to be corrected before imaging operations are able to resume. Resynchronizing the operation of the printing system to resume printing where the motion of the web was stopped may be difficult. Improvements in the operation of printers to address ink flow problems and web motion issues would be useful.